Kinetics of reactions in heterocycles. Part VI. Replacement of 2-alkylthio, 2-alkylsulphinyl, and 2-alkylsulphonyl groups from quinoxalines by methoxide ion
Abstract
Kinetic studies of the reactions of 2-alkylsulphonyl-, 2-alkylsulphinyl-, and 2-alkylthio-quinoxalines with sodium methoxide showed that for the methyl, ethyl, isopropyl, and t-butyl compounds a decreased reactivity was observed with increasing size of the group. This effect was least for the sulphides (1·8 fold difference) and greatest (140 fold) for sulphoxides. U.v. and 1H n.m.r. spectra are recorded and discussed.